In typical prior art automatic sorting apparatus by means of color, optical sensors inspect each fruit and generate a reject signal in response to the presence of a cull. The reject signal actuates or triggers removal mechanism which deflects or diverts the offending fruit from the pack line. Such optical sensing means however have generally been incapable of detecting a sufficiently large surface area of the fruit being tested or evaluated resulting in the passage of culls into the pack line. Or, if a sufficiently large surface area of the fruit is illuminated and detected, the rate of progress of the fruit through the pack line is undesirably slow. Of course, additional optical sensors and detectors could be added with a concomitant increase in cost, number of components and floor space being required.
The present invention employs a singulator conveyor or a plurality thereof, typically 3 or more, parallel disposed, each of which carry the fruit in single file from the loading chutes. Each singulator conveyor comprises roller conveyors rotatably mounted to chain drive means. The roller conveyors may be adjustably spaced along the chains in accordance with the size of fruit to cause each item of fruit to be carried by adjacent roller conveyors. The roller conveyors contact a moving fruit orientation belt which causes the roller conveyors to rotate accordingly. Rotating the rollers causes the fruit carried thereon to rotate in an opposite direction on stem axes, the axes of rotation and stem axes being substantially perpendicularly disposed to the direction of travel of the singulators.
Absent the fruit orientation belt, the roller conveyors would tend to transport the fruit therealong without the necessary rotation thereof, thus failing to orient the fruit in accordance with their stem axes, resulting in many fruit flipping off the conveyors when subjected to the momentary high spin section of the apparatus.
Thus, after the fruit are oriented, they encounter additional roller conveyors rotating at a substantially increased speed in a direction of rotation which continues the direction of rotation of the fruit as they leave the portion of the apparatus which has just oriented them. That is, the upper surfaces of the fruit during orientation and spin-acceleration, are moving in the same direction as the singulators are moving. Fruit thus rotating allow overhead cameras to "see" slightly more of the surface area of the fruit during passage therebelow for purposes of scanning.
More specifically, in parent application Ser. No. 430,083, the spin-acceleration section reversed the direction of rotation of the oriented fruit causing the fruit to occasionally bounce, upon entering or during spin-acceleration, and frequently causing succeeding fruit to similarly bounce. Bouncing fruit cannot readily be optically scanned by the apparatus shown and described in the present invention.
Citrus fruit such as lemons may be spun up to 6 or more revolutions per second for brief periods without damaging the fruit and yet allowing the fruit to turn about one complete revolution while being illuminated and scanned. Absent the orientation section, a lemon, for example, spin-accelerated at approximately 6 revolutions per second, would, in all probability, flip off the conveyor rollers or bounce thereon, if the fruit's direction of rotation were reversed by the spin-acceleration section. As mentioned above, by permitting the fruit to continue rotating in the same direction in the spin-acceleration section, flipping and bouncing of fruit have been eliminated.
After the surfaces of the fruit are scanned, and responsive signals generated in accordance with the scan, typically by means of a line scanning camera, ejection mechanism, for example, may be actuated in response to those signals to control deflection of the culls. The remaining packable fruit may optionally be separated into several packable grades or sorted in accordance with the teachings of the referenced Patent.
It is appreciated that the packable fruit of the present invention after cull deflection or diversion, may be sorted and/or graded in accordance with the teachings of the referenced patent or other known fruit packing principles or procedures.